In recent years, sales for essential oils and other topically applied oils have exploded. Topically applied oils are usually oils which are derived from, or include certain essential components or essences of different substances. Such topically applied oils are generally referred to as essential oils.
Essential oils, known as nature's living energy, are the natural, aromatic volatile liquids found in shrubs, flowers, trees, resins, fruit peels, rhizomes, roots, bushes, and seeds. The distinctive components in essential oils defend plants against insects, environmental conditions, and disease. They are also vital for a plant to grow, live, evolve, and adapt to its surroundings. Essential oils are extracted from aromatic plant sources via steam distillation, cold pressing, and other types of distillation. Essential oils are highly concentrated and far more potent than dry herbs. Other topically applied oils and fatty oils may include olive oil, almond oil, coconut oil, etc., and oils high in esters, such as jojoba oil, and waxes such as beeswax.
While essential oils often have a pleasant aroma, their phytochemical makeup is complex and their benefits vast—which make them much more than something that simply smells good. Historically, essential oils have played a prominent role in everyday life. With more than 200 references to aromatics, incense, and ointments throughout the Bible, essential oils are said to be used for anointing and healing the sick. Today, essential oils are used for aromatherapy, massage therapy, emotional health, personal care, nutritional supplements, household solutions, and much more.
Roller ball applicators have been used in many applications. However, roller ball applicators generally use a fairly pliable plastic housing to accommodate the ball in a press-fit assembly. Traditional roller ball assemblies are unsuitable for use with most topical oils, such as essential oils, particularly citrus essential oils (i.e., lemon, orange, grapefruit, bitter orange, yuzu, lime, bergamot, etc.), frankincense, high terpene oils, and other similar oils that can have a potent solvent effect, because the oils tend to impregnate plastics and relax the elasticity or swell the plastic, which often causes the roller ball to become excessively loose and potentially dislodge, or swell the roller ball and generally make plastic containers unsuitable. Additionally, essential oils tend to work as solvents with many plastics and can leach unwanted chemicals, pigments, residual monomers, and compounds from the plastics into the essential oils. Because of this, applicators for topical oils use different application methods and devices that do not require plastics that retain their material properties, and when using essential oils, generally avoid plastics altogether.